This invention relates to the field of industrial equipment. More particularly, it relates to a stabilizer for use in conjunction with industrial equipment that requires a stabilizer such as a rubber tired backhoe loader, a crane or a backhoe attachment mounted on, for instance, a skid steer loader.
It is known in the art to use stabilizers with a piece of industrial equipment that has a narrow wheel base and a high, and often shifting, center of gravity. For instance, rubber tired backhoe loaders typically utilize stabilizers. Generally, there are two main configurations for stabilizers; fold-down pivoting stabilizers, also known as outriggers, and vertical stabilizers which are useful for working in tight areas. In addition, skid steer loaders are frequently used for light industrial applications, frequently involving the use of a backhoe attachment for trenching and for light duty excavation. It is known in the art that a backhoe attachment includes either a vertical stabilizer or a fold down stabilizer, but not both. Heretofore, an operator had to choose what type of attachment was needed. If, for instance, a tractor has a state of the art fold-down stabilizer installed, but the work area is too narrow and demands a vertical stabilizer, or if a tractor has a vertical stabilizer, but has to dig a trench on a sloped area, the operator must decide whether to use a different piece of equipment or attempt to use equipment ill-suited for the task. This results in increased costs of operation and lost time due to the change in equipment.
There are several known art references that teach either vertical type supports or stabilizers for various types of equipment or fold-down pivoting stabilizers.
What has heretofore been missing from the art is a stabilizer that uses a standard hydraulic system and that is readily operable in either a vertical stabilizer mode or in a fold-down stabilizer mode.
Accordingly, it is an object of the present invention to provide a dual mode stabilizer, operable in either a fold-down stabilizer mode or a vertical stabilizer mode.
A further object of the present invention is to provide a dual mode stabilizer that is operable with a standard hydraulic system without requiring an additional hydraulic ram for each mode.
Yet another object of the present invention is to provide a dual mode stabilizer which is readily switchable from one mode to another while the equipment is in use.
Still another object of the present invention is to provide a dual mode stabilizer having adjustable mounting brackets.
Other objects and advantages over the prior art will become apparent to those skilled in the art upon reading the detailed description together with the drawings as described as follows.
In accordance with the various features of this invention, a dual mode stabilizer for a rubber tired backhoe loader and for a backhoe attachment for a skid steer loader, is provided. As used herein, tractor will refer to either a backhoe loader, including without limitation rubber tired backhoe loaders, or a skid steer loader. Those skilled in the art will recognize that the dual mode stabilizer of the present invention has utility with any type of industrial equipment that requires a stabilizer. The dual mode stabilizer can either be mounted directly on the frame of the tractor or on the backhoe attachment. Accordingly, reference herein to mounting or positioning relative to the backhoe attachment will be understood to be inclusive of mounting directly to the frame. Further, those skilled in the art will recognize that a dual-mode stabilizer can be mounted at each corner of the tractor. The dual mode stabilizer includes at least one base member rigidly fixed proximate at least one corner of the tractor proximate the backhoe. Each base member defines a channel for receiving a stabilizer arm assembly and includes a first anchor point disposed proximate the top of the base member and a stop disposed proximate the lower end of the base member. A stabilizer arm assembly is nested within and received by the base member. The stabilizer arm assembly includes a piston for actuating the stabilizer arm assembly, an outrigger arm member, a sliding arm member pivotally connected to the outrigger arm member so as to limit movement of the outrigger arm member with respect to the sliding arm member to rotational movement about a first pivot point proximate the lower end of the outrigger arm member and a first locking mechanism for preventing rotational movement of the outrigger arm member. A pin provided at the first pivot point engages the stop to limit the upward range of axial movement of the stabilizer arm assembly within the base member. In the preferred embodiment, the stop is defined by a clevis that receives the pin. Preferably, a bushing, engaged with the pin, engages the clevis so as to distribute the pressure at the point of contact over a greater surface area. Additionally, a brace is provided to reinforce the lower end of the base member proximate the clevis. The piston has a first end secured to the first anchor point and a second end secured to a second anchor point provided on the outrigger arm member.
The sliding arm member engages the base member and an associated mechanism is provided to limit movement of the sliding arm member within the base member to axial movement. A second locking mechanism is provided between the base member and the sliding arm member to prevent axial movement of the sliding arm member within the base member.
Actuation of the piston with the first locking mechanism engaged, preventing rotational movement of the outrigger arm, and the second locking mechanism released causes the stabilizer arm assembly to travel downwardly within base member thus providing operation in the vertical stabilizer mode. Contrariwise, actuation of the piston with the first locking mechanism released and the second locking mechanism engaged, preventing axial movement of the sliding arm member, causes the outrigger arm member to rotate about the first pivot point thereby providing operation in the fold down stabilizer mode. In the preferred embodiment, a foot member is provided at the distal end of each of the outrigger arm member and the sliding arm member.